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"Let us strive to make each moment beautiful."

Saint Francis DeSales

painting by Katie Bergenholtz

How Does Weight Affect the Speed at Which an Object Falls?

Take two tennis balls and hold them at chest level and drop them. Watch carefully as they land. Now use two different objects but use ones that are about the same shape and size, but of different weights, like a toy orange and a tennis ball. Are there any changes you would make to your experiment?"Galileo discovered that when he let two objects of different weights fall from the same height, they always landed at the same time. Everything has the same force of gravity pulling on it at the same time."(Real Science-4-Kids Physics Pre-Level I, Experiment 1: Falling Objects)Now, use a heavy book, and sheets of cardboard, construction paper and regular paper. Take turns holding the heaviest, and the next heaviest on down the line, and drop them together. For example, the first time you hold the book and the cardboard level with each other and drop them from the same level and see which one lands first. Next try the cardboard and the construction paper, and so on, on down the line. From this experiment one could conclude that heavier objects fall faster than lighter things.

But, is that really true?For the next experiment , you will use the same things you used last time, except you will also need a paper clip and a very small rock (one that weighs less than the cardboard.) Now, use the paper clip in one hand and the book, the cardboard, the construction paper and the regular paper in the other hand in successive tries. Note which falls first. Repeat this exercise except substitute the rock for the paper clip. Next, wad up the piece of regular paper into a ball. Repeat the same exercise with the ball of paper, using the book, the cardboard and the construction paper in the other hand in successive tries. You will probably see that the paperclip, the small rock and the paper ball all hit the ground first, with the possible exception of the paper ball and the book, which might land at the same time." Sir Isaac Newton was the first to use experiments to show that there is something called air resistance...the fact that air actually slows objects down as they fall. The heavier an object is, the less affected it is by air resistance. Newton actually showed that if you were able to eliminate air resistance, all objects fall at the same rate, regardless of weight, shape or any other characteristic...Newton's experiments, along with his mathematics (demonstrated this fact.)"*Another very important thing we can learn from these two experiments is that sometimes an experiment will appear to prove something, like that heavier objects fall faster than lighter ones. The second experiment, however, proved this conclusion to be wrong. This is a counter-example, or a example that contradicts a scientific conclusion. Our conclusion we made with the first experiment was contradicted by the second experiment, our counter-example.